What is Third-Party Ad Serving?

Many websites make their money using third-party ad serving companies.

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Third-party ad serving happens when you visit a website like allaboutcookies.org where the content of the site comes from the site, but the ads come from another server or website. Your browser assembles the differing information fed from differing sources so all items appear on the same page. For your browser to assemble the ads correctly, the website directs your browser to collect information from a different site's ad server. The third party website creates a cookie in your browser's folder as a result.

Why do websites use third-party ad serving companies?

Many websites, specially those providing free information or content, depend on advertising to continue operations.

Many of these sites don't have the technical and business development infrastructure to recruit their own advertiser accounts and serve their own ads.

As a result, they rely on other websites, third party advertisement serving companies, to recruit advertisers and serve those ads on publisher's sites.

This arrangement allows websites to focus on what they do best and save time and money.

So why do advertisers want to use cookies in this way?

Third-party ad serving cookies solve a lot of problems that normally arise in a situation where the website's visitor loads content from the website but the ads come from another site. Cookies help the ad serving website with the following:

* Cookies limit the number of times an ad is shown. This function comes in particularly handy when dealing with potentially annoying advertising forms like popup ads. Cookies ensure that a popup only shows up once per visit.

* Some ads are more effective when shown in a particular order or sequence. By helping the website you're viewing remember the pages you've visited during your browsing session, cookies enable ads to show up in a particular order.

* Advertisers need to know how many times their ads were shown on publisher's websites. Cookies allow the third party ad serving website to collect this information.

* Cookies allow advertisers to keep track of how many people visited the advertiser's websites through a click or a response on the ads shown by third party ad serving companies on publishers' websites. This feature helps both the ad serving company and the advertiser determine if a particular advertising campaign produced the desired results.

Do all websites use third-party ad serving?

Many websites rely on advertising to survive to provide free content to visitors. However, most do not have the infrastructure or resources to manage and run the advertising on their web pages. Instead they turn to third-party ad serving companies to provide the server space, campaign delivery and reporting facilities that they need.

Advertisers use third-party cookies to help advertising campaigns

Third-party ad serving companies provide useful, cost-effective services to websites that cannot manage advertising campaigns in-house. Advertisers like cookies to be used in the delivery of campaigns because they enable the following to happen without any personal information being collected:

Cookies limit the number of times that an advertisement is shown. This is particularly useful if pop-up ads are used, as cookies can ensure the same browser is not shown the same pop-up over and over again.
Enable a sequence of advertisements to be shown in the correct order.
Calculate how many unique web visitors have been shown an advertisement.
Calculate how many unique people visited a site as a direct response to an advertisement.